214 GOVERNMENT REGULATION AND WORKING PLANS 



Stand Graphics. — Under the leadership of Schaeffer," now conservator 

 at Vesoul, the routine descriptions of selection forest stands (which " had 

 to be done, were a great bore, and were never looked at") have been 

 largely replaced by graphics based on the stock sheet for each compart- 

 ment and for the forest. The objective is to picture the size classes of the 

 stand so the marking will be guided accordingly. This, perhaps, is the 

 feature of French mensuration and can be apphed in the United States 

 under intensive conditions. This method and its interpretation is 

 illustrated by Figs. 19 (a) and 19 (6) (after Schaeffer) which depict the 

 number of trees per hectare per (5 centimeter) two-inch diameter class at 

 breast height in fir-spruce selection forests. Certainly these graphics 

 would disclose inaccurate and imtrustworthy valuation surveys. 



No. 1 represents a pure high forest of ten acres, where there is not a 

 single tree less than 35 centimeters in diameter. It shows at once past 

 regeneration has been a failure. 



No. 2 is for a younger stand, similar in character and where no trees less 

 than 20 centimeters in diameter, breast-high, have been calipered. 



No. 3 represents a selection high forest, where the number of trees is 

 approximately inversely proportional to the squares of the diameters. 

 Consequently the curve approaches an hyperbola and the stand is more 

 satisfactory to the forester. 



No. 4 shows at once that the stocktaking was carelessly done, for evi- 

 dently those who were supposed to caliper did not scrupulously measure 

 all trees, but estimated a good many with the eye. This accounts for 

 the evident error in classifying more trees 20, 30, and 40 centimeters in 

 diameter than trees 25 or 35. In any compartment, of course, certain 

 diameter classes may predominate, but there would be no such irregu- 

 larity Uke the teeth of a saw as is shown in No. 4. 



No. 5 represents a forest of 10,000 acres and consequently unevennesses 

 have been eUminated but it is clear there are too few trees per acre, 

 especially in the larger age-size classes. 



No. 6 is a young pole stand where the large number of stems less than 

 20 centimeters in diameter are coming into the merchantable class. The 



removal from the woods will nearly always fall short of the French estimates, especially 

 in the large fir timber of the Jura, owing to defect and a certain amount of unavoidable 

 breakage. 



Conclusions. — Methods used are as nearly accurate as practicable, when properly 

 appUed, for standing saw timber, felled trees, and counted material. Cordwood esti- 

 mates are only approximate, depending on the experience of the estimator. 



The men are usually capable and experienced enough to apply the methods to 

 advantage. 



" Interpretation des Graphiques de Peuplements. A. Schaeffer, B. S. F. de F.-C. et 

 N., No. 6, 1912. Since the figures are merely to illustrate methods, no conversions to 

 American units were made. 



